MANILA: Philippine presidential candidate Rodrigo Duterte has widened his lead over rivals despite remarks about the rape and murder of an Australian missionary which sparked protests from diplomats, the Catholic church and women's groups.
Duterte, the tough-talking mayor of the southern city of Davao, emerged as the "clear frontrunner" in a survey which research institute Social Weather Stations (SWS) released Monday.
The candidate, who has promised mass killings of suspected criminals, saw his support rise from 27 percent of respondents in March to 33 percent in April, giving him a nine-point lead over second-placed Senator Grace Poe just two weeks before the vote.
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The survey was conducted from April 18-20, shortly after a video circulated showing Duterte making the remark about the missionary in a campaign hustings event.
Duterte, 71, had told laughing followers that the woman was so beautiful he wished he had been the first in line to rape her -- before she was murdered in a jail riot in his city in 1989.
SWS spokesman Leo Laroza said the apparent joke may have dented Duterte's popularity but did not stop him pulling ahead of his arrivals in the poll of 1,800 voters.
"Mayor Duterte has been steadily gaining ground. It's a clear lead. The joke could have affected him in such a way that his score could have even been higher had it not been for that news," he told AFP.
Francisco Magno, president of the Philippine Political Science Association, said the latest figures showed a substantial voting bloc was attracted to "strong man leadership".
It showed marked sympathy for his "one-issue campaign effort" against crime and illegal drugs, he added.
The survey also indicated that issues like women's rights and human rights in general were secondary for many.
"There is much to be desired about the quality of political education" in the country, Magno told AFP.
He said Duterte also benefited from having three rivals splitting the vote.
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If the anti-Duterte forces were eventually to unite behind one of them, that might determine the election result, said Magno.
Current President Benigno Aquino, the son of a former president, is constitutionally limited to a single six-year term. His preferred successor Mar Roxas -- the grandson of a former president -- trails badly in surveys.
Despite dramatic economic growth under Aquino, analysts say Duterte's appeal stems from popular disenchantment with the political elite in a nation where one in four still lives in poverty.
"Duterte's rise mirrors the revolt of the periphery," sociologist Randy David wrote in the Philippine Daily Inquirer on Sunday.
"It is difficult to see how, under a Duterte presidency, the country can avoid entering another period of political uncertainty."
Women's rights advocate Ana Maria Nemenzo said Duterte's ranking in the latest survey reflected poorly on Philippine culture.
"The culture of rape is very much prevalent, it is deep-seated in our machismo system. You can see the men seem to lap up this kind of talk," she told AFP.
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Nemenzo, head of WomanHealth Philipines, said that despite two female presidents in the past, the reaction to Duterte's "debasing" remarks showed the country still had far to go.
"If Duterte wins, it's going to be a tragedy, not only for the women's movement but for our country," she added.
Duterte's rape comments drew widespread condemnation including from the Australian and American ambassadors, while women's groups filed a complaint to the human rights commission.
But Duterte was undaunted, telling the diplomats to "shut their mouths" and warning he was prepared to sever ties with Canberra and Washington over the affair.
Another survey of 4,000 voters nationwide, taken by research group Pulse Asia before the remarks hit the headlines, also put Duterte in the lead with 34 percent ahead of Poe at just 22 percent.
Human rights groups have accused Duterte of leading vigilante death squads that have carried out over a thousand killings in Davao -- allegations he has boasted about.
If elected, he said, he would kill 100,000 criminals and dump so many in Manila Bay that the "fish will grow fat" from feeding on them.
In an election debate Sunday, he even vowed to kill his own children if they ever took drugs.